Golang : [json: cannot unmarshal object into Go value of type]
Un-marshalling JSON data from external sources can be challenging sometimes. Encountered this error message while working on the previous tutorial to display list of countries and the ISO2 codes.
json: cannot unmarshal object into Go value of type
Apparently, it was because the JSON data given by country.io has no fields identifiers. Only iso codes follow by country names. For instance :
{"BD": "Bangladesh", "BE": "Belgium" }
To deal(un-marshal) with this kind of data. First, we need to define a map expecting string and with the help of interface{}
For example,
resp, err := http.Get("http://country.io/names.json")
if err != nil {
fmt.Println(err)
os.Exit(1)
}
defer resp.Body.Close()
jsonCountriesData, err := ioutil.ReadAll(resp.Body)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
countriesMap := make(map[string]interface{})
// Decode JSON into our map
err = json.Unmarshal([]byte(jsonCountriesData), &countriesMap)
if err != nil {
println(err)
return
}
See for full source code example at : https://www.socketloop.com/tutorials/golang-display-list-of-countries-and-iso-codes
By Adam Ng
IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.
Advertisement
Tutorials
+8.4k Golang : Find correlation coefficient example
+9.7k Golang : Get UDP client IP address and differentiate clients by port number
+5k Golang : Shuffle array of list
+7.2k Golang : How To Use Panic and Recover
+12.9k Android Studio : Use image as AlertDialog title with custom layout example
+21.8k Golang : Randomly pick an item from a slice/array example
+26.6k Golang : Decode/unmarshal unknown JSON data type with map[string]interface
+5.2k Golang : Convert Chinese UTF8 characters to Pin Yin
+8.5k Golang : Quadratic example
+7.7k Golang : How to find out similarity between two strings with Jaro-Winkler Distance?
+6.7k Setting $GOPATH environment variable for Unix/Linux and Windows